Perioperative intravenous ketamine for acute postoperative pain in adults

Opioid-free versus opioid-based anesthesia in major spine surgery: a prospective, randomized, controlled clinical trial

BACKGROUND

Major spine surgery is associated with severe postoperative pain and increased opioid consumption. Opioid-free anesthesia (OFA) is thought to provide adequate intraoperative analgesia with reduced postoperative opioid consumption. The aim of this study is to compare the impact of intraoperative OFA approach to the conventional opioid-based anesthesia (OBA) on postoperative pain, opioid consumption, and related side effects in patients undergoing multilevel spinal fusion surgery.

METHODS

Forty-eight patients undergoing elective major spine surgery were randomly allocated to either receive intraoperative dexmedetomidine and lidocaine (OFA group) or fentanyl during induction and intraoperative remifentanil (OBA group). All patients received intraoperative sevoflurane, propofol, rocuronium, ketamine, dexamethasone, ondansetron and postoperative paracetamol and patient-controlled analgesia device set to deliver intravenous morphine for 48 hours after surgery. Postoperative pain was measured using numerical rating scale. Opioid side effects were documented, when present.

RESULTS

OFA group required less morphine in the first 24 hours post-surgery (17.28±12.25 mg versus 27.96±19.75 mg, P<0.05). The incidence of postoperative nausea and vomiting (PONV) was significantly lower in the OFA group. More patients in the OFA group required antihypertensive medications compared to patients in the OBA group (P<0.05). In the post anesthesia care unit, OFA patients had a significantly longer stay than OBA patients (114.1±49.33 min versus 89.96±30.71 min, P<0.05).

CONCLUSIONS

OFA can be an alternative to OBA in patients undergoing multilevel spine fusion surgery. OFA reduces opioids consumption in the first 24 hours and PONV.

Effects of intraoperative low-dose esketamine on postoperative pain after vestibular schwannoma resection: A prospective randomized, double-blind, placebo-controlled study

AIMS

Esketamine may reduce acute postoperative pain in several settings. However, the effects of low-dose esketamine on postoperative pain after vestibular schwannoma (VS) resection with propofol/remifentanil total intravenous anaesthesia (TIVA) are unclear. The aim of this study is to observe the effects of intraoperative low-dose esketamine on postoperative pain after vestibular schwannoma resection.

METHODS

This single-centre, randomized, placebo-controlled, double-blind trial included 90 adults undergoing VS resection via the retrosigmoid approach with TIVA. The patients were randomly allocated to two groups: esketamine or control (n = 45 in each group). Patients received low-dose esketamine (0.2 mg/kg) or a similar volume of normal saline after dural closure. The primary outcome was the pain score during movement (gentle head movement) at 24 h postoperatively. Secondary outcomes included recovery time, bispectral index (BIS) values and haemodynamic profiles during the first 30 min after esketamine administration, and adverse effects.

RESULTS

Low-dose esketamine did not reduce pain scores at rest (P > .05) or with movement (P > .05) within the first 24 h after surgery. Esketamine moderately increased BIS values for at least 30 min after administration (P < .0001) but did not affect heart rate (P = .992) or mean arterial blood pressure (P = .994). Esketamine prolonged extubation time (P = .042, 95% confidence interval: 0.08 to 4.42) and decreased the effect-site concentration of remifentanil at extubation (P = .001, 95% confidence interval: -0.53 to -0.15) but did not affect the time to resumption of spatial orientation. Postoperative nausea and vomiting rates did not differ between groups, and no hallucinations or excessive sedation was observed.

CONCLUSION

Intraoperative low-dose esketamine did not significantly reduce acute pain after VS resection with propofol/remifentanil TIVA. However, BIS values increased for at least 30 min after esketamine administration.

Perioperative Methadone for Spine Surgery: A Scoping Review

Complex spine surgery is associated with significant acute postoperative pain. Methadone possesses pharmacological properties that make it an attractive analgesic modality for major surgeries. This scoping review aimed to summarize the evidence for the perioperative use of methadone in adults undergoing complex spine surgery. The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR). A search was performed using MEDLINE, CINAHL, Cochrane Library, Scopus, Embase, and Joanna Briggs between January 1946 and April 2023. The initial search identified 317 citations, of which 12 met the criteria for inclusion in the review. There was significant heterogeneity in the doses, routes of administration, and timing of perioperative methadone administration in the included studies. On the basis of the available literature, methadone has been associated with reduced postoperative pain scores and reduced postoperative opioid consumption. Though safety concerns have been raised by observational studies, these have not been confirmed by prospective randomized studies. Further research is required to explore optimal methadone dosing regimens, the potential synergistic relationships between methadone and other pharmacological adjuncts, as well as the potential long-term antinociceptive benefits of perioperative methadone administration.

Opioid-free anesthesia using a combination of ketamine and dexmedetomidine in patients undergoing laparoscopic cholecystectomy: a randomized controlled trial

BACKGROUND

Opioids administered as bolus doses or continuous infusions are widely used for major and daycare surgeries. Opioid-free anesthesia is multimodal anesthesia and analgesia that does not use opioids, benefiting patients from opioid-related adverse effects. We compared the postoperative analgesic requirements of patients scheduled for elective laparoscopic cholecystectomy under opioid-free and opioid-based anesthesia.

METHODS

Study included 88 patients aged 18-60 years with American Society of Anesthesiologists physical status 1 and 2 who underwent elective laparoscopic cholecystectomy. Participants were randomly divided into two groups with 44 in each. The opioid-free group was administered an intravenous bolus of ketamine and dexmedetomidine, whereas fentanyl was used in opioid group. Primary outcome was to compare the total amount of fentanyl consumed by both groups during 6 h postoperative period. Episodes of postoperative nausea and vomiting (PONV) and vital signs were noted throughout the postoperative period to analyze the secondary outcomes.

RESULTS

Both groups had similar demographic characteristics. The opioid-free group required lesser analgesia within the first 2 h (61.4 ± 17.4 vs. 79.0 ± 19.4 of fentanyl, P < 0.001), which was statistically significant. However, fentanyl consumption was comparable between the groups at 6 h (152 ± 28.2 vs. 164 ± 33.4, P = 0.061). Compared with 4.5% of the participants in the opioid-free group, 34% of those in the opioid-based group developed moderate PONV.

CONCLUSIONS

Opioid-free anesthesia in patients undergoing laparoscopic cholecystectomy reduced the requirement of analgesia in first two-hour postoperative period and was associated with decreased PONV.

Effects of perioperative intravenous lidocaine and esketamine on the quality of recovery and emotional state of patients after thyroidectomy: A randomised, double-blind, controlled trial

Background and Aims

Perioperative intravenous (IV) infusions of lidocaine and esketamine reduce postoperative pain, but there are few studies on the quality of recovery and patients' emotional states postoperatively. We aimed to explore the effects of perioperative IV lidocaine and esketamine on the quality of recovery and emotional state after thyroidectomy.

Methods

In this randomised trial, 137 patients undergoing thyroidectomy were randomly assigned to three groups: a lidocaine group (Group L), an esketamine group (Group E) and a normal saline placebo group (Group C). The primary outcome was the Quality of Recovery 40 (QoR-40) on postoperative days (PODs) 1 and 2. The secondary outcomes included Self-Rating Anxiety Scale (SAS) and Self-Rating Depression Scale (SDS) scores on days 1 and 2 after surgery, pain scores, opioid consumption and incidence of postoperative nausea and vomiting (PONV). Statistical analysis was performed using the one-way analysis of variance (ANOVA), the Kruskal-Wallis and Chi-square tests.

Results

The global QoR-40 scores in groups L and E on POD 1 and POD 2 were significantly higher than in group C (P < 0.001). The SAS and SDS scores on POD 1 and POD 2 in groups L and E were significantly lower than in group C (P < 0.05). There were statistically significant differences in Numerical Rating Scale (NRS) scores among the three groups at 1 h, 2 h, 6 h and 12 h (P < 0.05).

Conclusion

Perioperative IV lidocaine and esketamine improve the quality of postoperative recovery and the emotional state of patients undergoing thyroidectomy.

Efficacy of Intravenous Administration of Esketamine in Preventing and Treating Rebound Pain After Thoracic Paravertebral Nerve Block: A Prospective Randomized, Double-Blind, Placebo-Controlled Trial

Purpose

Investigating the efficacy of intraoperative fractionated intravenous esketamine in the prevention of rebound pain after cessation of thoracic paravertebral nerve blockade.

Methods

One hundred and twenty patients who underwent elective thoracoscopic lobectomy were selected for the study and were randomly divided into two groups, the esketamine group was given 0.5 mg/kg and 0.3 mg/kg of esketamine at the induction of anaesthesia and 30 minutes before the end of the operation, respectively, and the control group was given an equal amount of saline. The incidence of rebound pain (RP) 7 days after surgery and postoperative recovery were compared between the two groups.

Results

The NRS pain scores at 24 and 48 hours postoperatively in the esketamine group were significantly lower than those in the control group (P < 0.05). The incidence of postoperative rebound pain was significantly lower in the esketamine group than in the control group (P < 0.05). The consumption of sufentanil was less in the esketamine group in the postoperative 48 hours (P < 0.05). Postoperative recovery was compared between the two groups and the difference was not statistically significant.

Conclusion

Intravenous esketamine reduces postoperative pain scores, decreases the incidence of rebound pain after cessation of thoracic paravertebral block, and reduces opioid consumption.

Effect of esketamine-based opioid-sparing anesthesia strategy on postoperative pain and recovery quality in patients undergoing total laparoscopic hysterectomy: A randomized controlled trail

Objective

Opioid-sparing anesthesia reduces intraoperative use of opioids and postoperative adverse reactions. The current study investigated the effect of esketamine-based opioid-sparing anesthesia on total laparoscopic hysterectomy patients' recovery.

Methods

Ninety patients undergoing total laparoscopic hysterectomy were randomly assigned to esketamine-based group (group K) or opioid-based group (group C). The allocation to groups was unknown to patients, surgeons, and postoperative medical staff. The inability to implement blinding for anesthesiologists was due to the distinct procedures followed by the various groups while administering drugs. The QoR-40 and VAS were used to measure recovery quality. Postoperative adverse events, perioperative opioid consumption, and intraoperative hemodynamics were secondary endpoints.

Results

There was an absence of notable discrepancy in the baseline data observed between the two groups. The QoR-40 scores exhibited greater values in group K when compared to group C on the first day following the surgical procedure (160.91 ± 9.11 vs 151.47 ± 8.35, respectively; mean difference 9.44 [95 %CI: 5.78-13.11]; P < 0.01). Within 24 h of surgery, the VAS score of group K was lower at rest and during movement. (P < 0.05 for each). Group K had much lower rates of nausea and vomiting within 24 h of surgery. (P < 0.05 for each). Group K received significantly lower total doses of sufentanil and remifentanil than group C. (17.28 ± 2.59 vs 43.43 ± 3.52; 0.51 ± 0.15 vs 1.24 ± 0.24). The proportion of patients who used ephedrine in surgery was higher in group C than in group K (P < 0.05).

Conclusions

Esketamine-based opioid-sparing anesthesia strategy is feasible and enhanced recuperation following surgery by decreasing adverse effects associated with opioids and pain scores compared to an opioid-based anesthetic regimen.

The impact of ketamine on outcomes in critically ill patients: a systematic review with meta-analysis and trial sequential analysis of randomized controlled trials

BACKGROUND

This meta-analysis aims to evaluate the effects of ketamine in critically ill intensive care unit (ICU) patients.

METHODS

We searched for randomized controlled trials (RCTs) in PubMed, Scopus, and the Cochrane Library; the search was performed initially in January but was repeated in December of 2023. We focused on ICU patients of any age. We included studies that compared ketamine with other traditional agents used in the ICU. We synthesized evidence using RevMan v5.4 and presented the results as forest plots. We also used trial sequential analysis (TSA) software v. 0.9.5.10 Beta and presented results as TSA plots. For synthesizing results, we used a random-effects model and reported differences in outcomes of two groups in terms of mean difference (MD), standardized MD, and risk ratio with 95% confidence interval. We assessed the risk of bias using the Cochrane RoB tool for RCTs. Our outcomes were mortality, pain, opioid and midazolam requirements, delirium rates, and ICU length of stay.

RESULTS

Twelve RCTs involving 805 ICU patients (ketamine group, n=398; control group, n=407) were included in the meta-analysis. The ketamine group was not superior to the control group in terms of mortality (in five studies with 318 patients), pain (two studies with 129 patients), mean and cumulative opioid consumption (six studies with 494 patients), midazolam consumption (six studies with 304 patients), and ICU length of stay (three studies with 270 patients). However, the model favored the ketamine group over the control group in delirium rate (four studies with 358 patients). This result is significant in terms of conventional boundaries (alpha=5%) but is not robust in sequential analysis. The applicability of the findings is limited by the small number of patients pooled for each outcome.

CONCLUSIONS

Our meta-analysis did not demonstrate differences between ketamine and control groups regarding any outcome except delirium rate, where the model favored the ketamine group over the control group. However, this result is not robust as sensitivity analysis and trial sequential analysis suggest that more RCTs should be conducted in the future.

Novel Targets and Drug Delivery System in the Treatment of Postoperative Pain: Recent Studies and Clinical Advancement

Pain is generated by a small number of peripheral targets. These can be made more sensitive by inflammatory mediators. The number of opioids prescribed to the patients can be reduced dramatically with better pain management. Any therapy that safely and reliably provides extended analgesia and is flexible enough to facilitate a diverse array of release profiles would be useful for improving patient comfort, quality of care, and compliance after surgical procedures. Comparisons are made between new and traditional methods, and the current state of development has been discussed; taking into account the availability of molecular and cellular level data, preclinical and clinical data, and early post-market data. There are a number of benefits associated with the use of nanotechnology in the delivery of analgesics to specific areas of the body. Nanoparticles are able to transport drugs to inaccessible bodily areas because of their small molecular size. This review focuses on targets that act specifically or primarily on sensory neurons, as well as inflammatory mediators that have been shown to have an analgesic effect as a side effect of their anti- inflammatory properties. New, regulated post-operative pain management devices that use existing polymeric systems were presented in this article, along with the areas for potential development. Analgesic treatments, both pharmacological and non-pharmacological, have also been discussed.

Efficacy of memantine premedication in alleviating postoperative pain- A systematic review and meta-analysis

Many premedication agents with opioid-sparing properties have been used in patients undergoing various elective surgeries. Memantine is an N-methyl-D-aspartate (NMDA) receptor antagonist that has been used by many researchers as an opioid-sparing strategy. Various databases like PubMed, Scopus, Cochrane Library, and clinicaltrials.gov were searched after registering the review protocol in PROSPERO for randomized-controlled trials (RCTs) that investigated the efficacy and safety of memantine premedication in adult patients undergoing various elective surgeries. The risk of bias (RoB-2) scale was used to assess the quality of evidence. From the 225 articles that were identified after a database search, 3 studies were included for a qualitative systematic review and a quantitative meta-analysis. The pooled analysis revealed that the use of memantine provided better pain scores at 2nd (mean difference: -0.82, 95% CI: -1.60, -0.05, P = 0.04) with significant heterogeneity (P = 0.06; I² =71%), and 6 hours postoperatively (mean difference: -1.80, 95% CI: -2.23, -1.37, P < 0.00001), but not at 1 hour. The sedation scores at 1 hour were higher in the memantine group but comparable in the 2nd hour. The number of doses of rescue analgesia and nausea/vomiting in the postoperative period was comparable in both groups. The results of this review suggest that memantine premedication could provide better pain scores in the immediate postoperative period with acceptable adverse effects. However, the current evidence is insufficient to suggest the routine use of memantine as a premedication before elective surgeries.

Analgesic Effect of Intraoperative Intravenous S(+)-Ketamine During Total Knee Arthroplasty Surgery: Study Protocol for a Randomized Controlled Clinical Trial

BACKGROUND

Total knee arthroplasty (TKA) is currently the main treatment for end-stage knee disease. The number of cases of TKA in China increased from 53,880 in 2011 to 374,833 in 2019, representing a 5.9-fold increase. Moderate to severe pain often occurs after TKA, which seriously affects postoperative rehabilitation, patient satisfaction, and overall outcome. Multimodal analgesia is considered the ideal solution. Adequate postoperative analgesia can not only reduce pain, opioid consumption, and, consequently, opioid-related adverse events, but can also reduce the length of hospital stay and costs and improve rehabilitation and patient satisfaction.

OBJECTIVE

Effective multimodal pain management in the early postoperative period is essential for anesthesiologists. Additional studies have demonstrated that a low-dose intravenous infusion of ketamine can be administered as an adjuvant drug to alleviate acute postoperative pain. Therefore, we aim to appraise the efficacy and safety of intraoperative intravenous injection of S(+)-ketamine to relieve acute pain after TKA in older patients.

METHODS

This is a protocol for a randomized, placebo-controlled trial. A total of 144 participants aged 65 years and older undergoing TKA will be randomly allocated into the S(+)-ketamine and placebo groups in a 1:1 ratio. S(+)-ketamine or the placebo will be intravenously administered at 0.3 mg/kg/h during the operation by anesthesiologists. Blinded evaluation by trained investigators will be completed at 2 hours, 24 hours, and 48 hours after surgery. The primary outcome measure will be the numeric rating scale score at rest and movement at 24 hours after surgery. The secondary outcomes will include the numeric rating scale scores at rest and movement at 2 hours and 48 hours after surgery, the number of patients who require additional analgesics during the first 48 hours after operation, the total consumption of opioids or nonsteroid anti-inflammatory drugs during the first 48 hours after operation, and adverse events at 2, 24, and 48 hours after operation.

RESULTS

The protocol was registered at Clinical Trials.gov on February 26, 2022. It was performed in accordance with the approved guidelines and regulations of the participating institutions. Recruitment began in April 2022. Data collection is expected to conclude in September 2024. Study completion is expected in December 2024.

CONCLUSIONS

A randomized, controlled, clinical study was designed to observe the analgesic effect of intraoperative intravenous administration of a lower dose of S(+)-ketamine (0.3 mg/kg/h) in older patients after TKA surgery. The protocol will appraise the efficacy and safety of intraoperative intravenous injection of S(+)-ketamine to relieve acute pain after TKA in older patients who may benefit from the administration of S(+)-ketamine.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05289050; https://clinicaltrials.gov/ct2/show/NCT05289050.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/53063.

Ketamine for postoperative pain treatment in spinal surgery: Systematic review with meta-analysis and trial sequential analysis

AIM

We aimed to assess the beneficial and harmful effects of perioperative pain treatment with ketamine in patients undergoing spinal surgery.

METHODS

We searched Medline, Embase, and CENTRAL from inception until 15 February 2023 for randomised clinical trials comparing ketamine with placebo or no intervention in patients undergoing spinal surgery. The primary outcomes were cumulative opioid consumption at 24 h postoperatively and serious adverse events. We adhered to recommendations of the Cochrane Collaboration and performed meta-analysis, Trial Sequential Analysis (TSA) to assess the risks of random errors, risk of bias assessment to evaluate the risks of systematic errors, and used the Grading of Recommendations Assessment, Development and Evaluation (GRADE).

RESULTS

We included a total of 28 randomised clinical trials enrolling 2110 participants providing data for our pre-defined outcomes. Twenty-three trials enrolled adult participants and 5 trials enrolled paediatric participants. Three trials were at low risk of bias. Meta-analysis and TSA of trials including adults showed that ketamine versus placebo or no intervention seemed to reduce the cumulative 24-h opioid consumption (mean difference -17.57 mg; TSA-adjusted 95% confidence interval, -24.22 to -10.92; p < .01; low certainty of evidence), and there was no evidence of a difference of ketamine versus placebo or no intervention on the risk of serious adverse events (risk ratio 2.16; 96.7% confidence interval, 0.35 to 13.17; p = .36; very low certainty of evidence).

CONCLUSION

In adults undergoing spinal surgery, ketamine may reduce cumulative 24-h opioid consumption. Ketamine may increase the occurrence of serious adverse events, but the evidence was very uncertain.

The use of ketamine infusion to dramatically reduce opioid requirements in a patient whose high-dose intrathecal opioid pump was inadvertently cut during surgery

BACKGROUND

Chronic opioid therapy may lead to high level tolerance development, hyperalgesia, and central sensitization, which further complicates long-term therapeutic management of chronic pain patients. In this case, we encounter a patient who was receiving over 15,000 morphine milligram equivalents through their intrathecal pain pump. Unfortunately, the intrathecal pump was inadvertently cut during a spinal surgery. It was deemed unsafe to delivery IV equivalent opioid therapy in this case; instead, the patient was admitted to the ICU and given a four-day ketamine infusion.

METHOD

The patient was started on a ketamine infusion at a rate of 0.5mg/kg/h, which was continued for three days. On the fourth day, the infusion rate was tapered over 12 h before being completely stopped. No coinciding opioid therapy was given during this time, which was only restarted in the outpatient setting.

RESULTS

Despite chronic high levels of opioid therapy immediately prior to the ketamine infusion, the patient did not experience florid withdrawals during the infusion period. Additionally, the patient experienced remarkable improvement in their subjective pain rating, which decreased from 9 to 3-4 on an 11-point Number Rating Scale, while simultaneously being managed on an MME <100. These results were sustained through a 6-month follow-up period.

CONCLUSION

Ketamine may play an important role in attenuating not only tolerance but also acute withdrawal in a setting where rapid or instant weaning from high dose chronic opioid therapy is needed.

Effect of Intravenous Ketamine Infusion on Hemodynamics of Patients Undergoing Cesarean Delivery after Spinal Anaesthesia: A Randomized, Double-Blind, Controlled Trial

Objective

Hypotension is the most frequent side effect of intrathecal anaesthesia, with an incidence of more than 80%. Following neuraxial anaesthesia, perioperative shivering is a serious complication affecting 40-60% of patients undergoing surgery. This study aimed to determine the effectiveness of low-dose ketamine on blood pressure in patients undergoing cesarean delivery after spinal anaesthesia.

Methods

We included 126 female patients undergoing cesarean deliveries, American Society of Anesthesiologists (ASA)-(II and III), and aged 21-40 selected from the outpatient clinics of the anaesthesia department. Patients were randomized to two groups; Group K (63 patients), who received 0.3 mg kg-1 of ketamine IV diluted to 10 mL, followed by an infusion of 0.1 mg kg-1 h-1. Group C (Controlled) (63 patients) received 10 mL of normal saline, followed by an infusion of 0.1 mL kg-1 h-1, which started before spinal anaesthesia.

Results

Compared with the saline group, the average heart rate, blood pressure, and level of sedation were significantly higher in the ketamine group (P < 0.05). The ketamine group reported a significantly lower incidence of shivering (P < 0.01). The ketamine groups exhibited significantly less mild or severe hypotension (P < 0.05). There was no significant difference between the two groups in terms of nystagmus, diplopia, hallucinations, or neonatal outcomes (P > 0.05).

Conclusion

Ketamine decreases the incidence of hypotension and shivering in patients undergoing spinal anaesthesia during cesarean delivery. In addition, it resulted in improved sedation for the mother and prolonged postoperative analgesia without neonatal illness.

Safety considerations with the current ambulatory trends: more complicated procedures and more complicated patients

In the last quarter of a century, the backdrop of appropriate ambulatory and office-based surgeries has changed dramatically. Procedures that were traditionally done in hospitals or patients being admitted after surgery are migrating to the outpatient setting and being discharged on the same day, respectively, at a remarkable rate. In the face of this exponential growth, anesthesiologists are constantly being challenged to maintain patient safety by understanding the appropriate patient selection, procedure, and surgical location. Recently published literature supports the trend of higher, more medically complex patients, and more complicated procedures shifting towards the outpatient arena. Several reasons that may account for this include cost incentives, advancement in anesthesia techniques, enhanced recovery after surgery (ERAS) protocols, and increased patient satisfaction. Anesthesiologists must understand that there is a lack of standardized state regulations regarding ambulatory surgery centers (ASCs) and office-based surgery (OBS) centers. Current and recently graduated anesthesiologists should be aware of the safety concerns related to the various non-hospital-based locations, the sustained growth and demand for anesthesia in the office, and the expansion of mobile anesthesia practices in the US in order to keep up and practice safely with the professional trends. Continuing procedural ambulatory shifts will require ongoing outcomes research, likely prospective in nature, on these novel outpatient procedures, in order to develop risk stratification and prediction models for the selection of the proper patient, procedure, and surgery location.

Effect of opioid-free anesthesia on the incidence of postoperative nausea and vomiting: A meta-analysis of randomized controlled studies

BACKGROUND

Research on opioid-free anesthesia has increased in recent years; however, it has never been determined whether it is more beneficial than opioid anesthesia. This meta-analysis was primarily used to assess the effect of opioid-free anesthesia compared with opioid anesthesia on the incidence of postoperative nausea and vomiting.

METHODS

We searched the electronic databases of PubMed, the Cochrane Library, Web of Science and Embase from 2014 to 2022 to identify relevant articles and extract relevant data. The incidence of postoperative nausea and vomiting, time to extubation, pain score at 24 hours postoperatively, and time to first postoperative rescue analgesia were compared between patients receiving opioid-free anesthesia and those receiving standard opioid anesthesia. Differences in the incidence of postoperative nausea and vomiting were evaluated using risk ratios (95% confidence interval [CI]). The significance of the differences was assessed using mean differences and 95% CI. The heterogeneity of the subject trials was evaluated using the I2 test. Statistical analysis was performed using the RevMan 5.4 software.

RESULTS

Fourteen randomized controlled trials, including 1354 participants, were evaluated in the meta-analysis. As seen in the forest plot, the OFA group had a lower risk of postoperative nausea and vomiting than the control group (risk ratios = 0.41, 95% CI: 0.33-0.51, P < .00001; n = 1354), and the meta-analysis also found that the OFA group had lower postoperative analgesia scores at 24 hours (P < .000001), but time to extubation (P = .14) and first postoperative resuscitation analgesia time (P < .54) were not significantly different.

CONCLUSIONS

Opioid-free anesthesia reduces the incidence of postoperative nausea and vomiting while providing adequate analgesia without interfering with postoperative awakening.

A subanesthetic dose of esketamine combined with hip peripheral nerve block has good sedative and analgesic effects in elderly patients undergoing total hip arthroplasty: A randomized-controlled trial

OBJECTIVES

This study aims to observe the postoperative anesthetic effect of esketamine combined with hip capsule peripheral nerve block (PNB) in elderly patients undergoing total hip arthroplasty (THA).

PATIENTS AND METHODS

A total of 120 elderly patients (67 males, 53 females; mean age: 72.5±6.1 years; range, 60 to 89 years) who underwent THA between January 2020 and May 2021 were randomly divided into three groups including 40 patients in each group. The observation group (Group A) was treated with a subanesthetic dose of esketamine combined with hip capsule PNB; control group (Group B) was treated with a subanesthetic dose of esketamine combined with lumbar plexus block; and control group (Group C) was treated with a subanesthetic dose of esketamine for general anesthesia. The onset time of anesthesia, duration of block, postoperative recovery time, postoperative extubation time, mean arterial pressure (MAP), heart rate (HR) indexes, Visual Analog Scale (VAS) and Ramsay Sedation Scale (RSS) scores were recorded.

RESULTS

The onset time of anesthesia, duration of block, postoperative recovery time and postoperative extubation time in Group A were significantly lower than those in Groups B and C (p<0.001). Compared to Groups B and C, the MAP was higher at T1-T3 and the HR was significantly higher at T0-T1 (p<0.05) in Group A. The VAS scores after the operation in Group A were significantly lower than those in Groups B and C (p<0.001), and the RSS scores after the operation were significantly higher in this group than in Groups B and C (p<0.001).

CONCLUSION

A subanesthetic dose of esketamine combined with hip capsule PNB for elderly patients undergoing THA has better postoperative analgesic effects.

Perioperative Use of Ketamine

PURPOSE OF REVIEW

Postoperative pain continues to be one of the most common challenges following surgeries. Multimodal analgesia has been of particular focus as non-opioid alternatives have been encouraged due to concerns of the opioid epidemic. Ketamine has been an especially useful adjunct in multimodal pain regimens within the past few decades. This article highlights the current use and advances surrounding the perioperative use of ketamine.

RECENT FINDINGS

Ketamine has antidepressive effects at subanesthetic doses. Intraoperative ketamine may be beneficial in reducing postoperative depression. Additionally, newer studies are exploring whether ketamine can be useful in reducing postoperative sleep disturbances. Ketamine continues to be a great tool in perioperative pain control, especially during an opioid epidemic. As its use continues to expand and gain more popularity in the perioperative period, more research could shed light on the additional nonanalgesic benefits of ketamine use.

Topical ophthalmic anesthetics for corneal abrasions

BACKGROUND

Despite potential analgesic benefits from topical ophthalmic amides and esters, their outpatient use has become of concern because of the potential for abuse and ophthalmic complications.

OBJECTIVES

To assess the effectiveness and safety of topical ophthalmic anesthetics compared with placebo or other treatments in persons with corneal abrasions.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL); MEDLINE; Embase.com; Latin American and Caribbean Health Sciences (LILACS); ClinicalTrials.gov; and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP), without restriction on language or year of publication. The search was performed on 10 February 2023.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) of topical ophthalmic anesthetics alone or in combination with another treatment (e.g. nonsteroidal anti-inflammatory drugs (NSAIDs)) versus a non-anesthetic control group (e.g. placebo, non-treatment, or alternative treatment). We included trials that enrolled participants of all ages who had corneal abrasions within 48 hours of presentation.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodology.

MAIN RESULTS

We included nine parallel-group RCTs with a total of 556 participants (median number of participants per study: 45, interquartile range (IQR) 44 to 74), conducted in eight countries: Australia, Canada, France, South Korea, Turkey, New Zealand, UK, and USA. Study characteristics and risk of bias Four RCTs (314 participants) investigated post-traumatic corneal abrasions diagnosed in the emergency department setting. Five trials described 242 participants from ophthalmology surgery centers with post-surgical corneal defects: four from photorefractive keratectomy (PRK) and one from pterygium surgery. Study duration ranged from two days to six months, the most common being one week (four RCTs). Treatment duration ranged from three hours to one week (nine RCTs); the majority were between 24 and 48 hours (five RCTs). The age of participants was reported in eight studies, ranging from 17 to 74 years of age. Only one participant in one trial was under 18 years of age. Of four studies that reported funding sources, none was industry-sponsored. We judged a high risk of bias in one trial with respect to the outcome pain control by 48 hours, and in five of seven trials with respect to the outcome complications at the furthest time point. The domain for which we assessed studies to be at the highest risk of bias was missing or selective reporting of outcome data. Findings The treatments investigated included topical anesthetics compared with placebo, topical anesthetic compared with NSAID (post-surgical cases), and topical anesthetics plus NSAID compared with placebo (post-surgical cases). Pain control by 24 hours In all studies, self-reported pain outcomes were on a 10-point scale, where lower numbers represent less pain. In post-surgical trials, topical anesthetics provided a moderate reduction in self-reported pain at 24 hours compared with placebo of 1.28 points on a 10-point scale (mean difference (MD) -1.28, 95% confidence interval (CI) -1.76 to -0.80; 3 RCTs, 119 participants). In the post-trauma participants, there may be little or no difference in effect (MD -0.04, 95% CI -0.10 to 0.02; 1 RCT, 76 participants). Compared with NSAID in post-surgical participants, topical anesthetics resulted in a slight increase in pain at 24 hours (MD 0.82, 95% CI 0.01 to 1.63; 1 RCT, 74 participants). One RCT compared topical anesthetics plus NSAID to placebo. There may be a large reduction in pain at 24 hours with topical anesthetics plus NSAID in post-surgical participants, but the evidence to support this large effect is very uncertain (MD -5.72, 95% CI -7.35 to -4.09; 1 RCT, 30 participants; very low-certainty evidence). Pain control by 48 hours Compared with placebo, topical anesthetics reduced post-trauma pain substantially by 48 hours (MD -5.68, 95% CI -6.38 to -4.98; 1 RCT, 111 participants) but had little to no effect on post-surgical pain (MD 0.41, 95% CI -0.45 to 1.27; 1 RCT, 44 participants), although the evidence is very uncertain. Pain control by 72 hours One post-surgical RCT showed little or no effect of topical anesthetics compared with placebo by 72 hours (MD 0.49, 95% CI -0.06 to 1.04; 44 participants; very low-certainty evidence). Proportion of participants with unresolved epithelial defects When compared with placebo or NSAID, topical anesthetics increased the number of participants without complete resolution of defects in trials of post-trauma participants (risk ratio (RR) 1.37, 95% CI 0.78 to 2.42; 3 RCTs, 221 participants; very low-certainty evidence). The proportion of placebo-treated post-surgical participants with unresolved epithelial defects at 24 to 72 hours was lower when compared with those assigned to topical anesthetics (RR 0.14, 95% CI 0.01 to 2.55; 1 RCT, 30 participants; very low-certainty evidence) or topical anesthetics plus NSAID (RR 0.33, 95% CI 0.04 to 2.85; 1 RCT, 30 participants; very low-certainty evidence). Proportion of participants with complications at the longest follow-up When compared with placebo or NSAID, topical anesthetics resulted in a higher proportion of post-trauma participants with complications at up to two weeks (RR 1.13, 95% CI 0.23 to 5.46; 3 RCTs, 242 participants) and post-surgical participants with complications at up to one week (RR 7.00, 95% CI 0.38 to 128.02; 1 RCT, 44 participants). When topical anesthetic plus NSAID was compared with placebo, no complications were reported in either treatment arm up to one week post-surgery (risk difference (RD) 0.00, 95% CI -0.12 to 0.12; 1 RCT, 30 participants). The evidence is very uncertain for safety outcomes. Quality of life None of the included trials assessed quality of life outcomes.

AUTHORS' CONCLUSIONS

Despite topical anesthetics providing excellent pain control in the intraoperative setting, the currently available evidence provides little or no certainty about their efficacy for reducing ocular pain in the initial 24 to 72 hours after a corneal abrasion, whether from unintentional trauma or surgery. We have very low confidence in this evidence as a basis to recommend topical anesthetics as an efficacious treatment modality to relieve pain from corneal abrasions. We also found no evidence of a substantial effect on epithelial healing up to 72 hours or a reduction in ocular complications when we compared anesthetics alone or with NSAIDs versus placebo.

Effect of Intraoperative Infusion of Esketamine on Quality of Postoperative Recovery in Patients Undergoing Laparoscopic Bariatric Surgery: A Randomized Controlled Trial

INTRODUCTION

This study aims to evaluate the efficacy of esketamine on postoperative recovery quality after laparoscopic bariatric surgery.

METHODS

Patients (n = 74) scheduled for laparoscopic bariatric surgery were randomly divided into two groups: the esketamine group (group E: 0.5 mg/kg/h infusion, i.e., 0.2 mL/kg/h) or the control group (group C: 0.2 mL/kg/h normal saline infusion). The infusions were stopped 20 min before the end of the procedure. The primary outcome was the Quality of Recovery-40 (QoR-40) score on postoperative day 1 (POD 1). The secondary outcomes included QoR-40 scores on PODs 2 and 7, Numeric Rating Scale (NRS) on PODs 1, 2, and 7, time to extubation, additional postoperative analgesic use, length of hospital stay, and time to first exhaust. Additonally, the safety indices were also recorded, including hemodynamic profile, perioperative anesthesia index (Ai), utilization of vasoactive drugs or urapidil, and side effects.

RESULTS

All in all, 70 of the 74 patients completed the study, 35 in each group. The difference of QoR-40 scores on POD 1 was both statistically and clinically significant [difference 7.21, 95% confidence interval (CI) 5.17, 9.25, p < 0.001]. The difference of QoR-40 on POD 2 was statistically significant but clinically insignificant (difference 4.81, 95% CI 2.69, 6.92, p < 0.001). The difference of NRS scores on POD 1 was statistically significant (difference -1.23, 95% CI -2.36, -0.10, p = 0.033). Compared with group C, group E had a lower utilization rate of phenylephrine and higher Ai values (p < 0.05). There was no statistical difference between the two groups on other measures.

CONCLUSION

Continuous ketamine infusion seems to be safe and well tolerated in laparoscopic bariatric surgery. It improved the quality of postoperative recovery and reduced pain on POD 1. In spite of the increased Ai value during the surgery, it also provided better hemodynamics with less usage of phenylephrine.

Perioperative opioid-minimization approach as a useful protocol in the management of patients with Ehlers-Danlos syndrome-hypermobility type, craniocervical instability and severe chronic pain who are to undergo occipito-cervical fixation

Patients suffering from connective tissue disorders like Ehlers-Danlos syndrome hypermobility type/joint hypermobility syndrome (EDS-HT/JHS) may be affected by craniocervical instability (CCI). These patients experience myalgic encephalomyelitis, chronic fatigue, depression, extreme occipital-cervical pain, and severe widespread pain that is difficult to relieve with opioids. This complex and painful condition can be explained by the development of chronic neuroinflammation, opioid-induced hyperalgesia, and central sensitization. Given the challenges in treating such severe physical pain, we evaluated all the analgesic methods previously used in the perioperative setting, and updated information was presented. It covers important physiopathological aspects for the perioperative care of patients with EDS-HT/JHS and CCI undergoing occipital-cervical/thoracic fixation/fusion. Moreover, a change of paradigm from the current opioid-based management of anesthesia/analgesia in these patients to the perioperative opioid minimization strategies used by the authors was analyzed and proposed as follow-up considerations from our previous case series. These strategies are based on total-intravenous opioid-free anesthesia, multimodal analgesia, and a postoperative combination of anti-hyperalgesic coadjuvants (lidocaine, ketamine, and dexmedetomidine) with an opioid-sparing effect.

Postintensive Care Syndrome: Feasibly Bridging Care at a Tertiary Trauma Center

BACKGROUND

Advancements in critical care management have improved mortality rates of trauma patients; however, research has identified physical and psychological impairments that remain with patients for an extended time. Cognitive impairments, anxiety, stress, depression, and weakness in the postintensive care phase are an impetus for trauma centers to examine their ability to improve patient outcomes.

OBJECTIVE

This article describes one center's efforts to intervene to address postintensive care syndrome in trauma patients.

METHODS

This article describes implementing aspects of the Society of Critical Care Medicine's liberation bundle to address postintensive care syndrome in trauma patients.

RESULTS

The implementation of the liberation bundle initiatives was successful and well received by trauma staff, patients, and families. It requires strong multidisciplinary commitment and adequate staffing. Continued focus and retraining are requirements in the face of staff turnover and shortages, which are real-world barriers.

CONCLUSIONS

Implementation of the liberation bundle was feasible. Although the initiatives were positively received by trauma patients and their families, we identified a gap in the availability of long-term outpatient services for trauma patients after discharge from the hospital.

International Consensus Statement on Obstructive Sleep Apnea

BACKGROUND

Evaluation and interpretation of the literature on obstructive sleep apnea (OSA) allows for consolidation and determination of the key factors important for clinical management of the adult OSA patient. Toward this goal, an international collaborative of multidisciplinary experts in sleep apnea evaluation and treatment have produced the International Consensus statement on Obstructive Sleep Apnea (ICS:OSA).

METHODS

Using previously defined methodology, focal topics in OSA were assigned as literature review (LR), evidence-based review (EBR), or evidence-based review with recommendations (EBR-R) formats. Each topic incorporated the available and relevant evidence which was summarized and graded on study quality. Each topic and section underwent iterative review and the ICS:OSA was created and reviewed by all authors for consensus.

RESULTS

The ICS:OSA addresses OSA syndrome definitions, pathophysiology, epidemiology, risk factors for disease, screening methods, diagnostic testing types, multiple treatment modalities, and effects of OSA treatment on multiple OSA-associated comorbidities. Specific focus on outcomes with positive airway pressure (PAP) and surgical treatments were evaluated.

CONCLUSION

This review of the literature consolidates the available knowledge and identifies the limitations of the current evidence on OSA. This effort aims to create a resource for OSA evidence-based practice and identify future research needs. Knowledge gaps and research opportunities include improving the metrics of OSA disease, determining the optimal OSA screening paradigms, developing strategies for PAP adherence and longitudinal care, enhancing selection of PAP alternatives and surgery, understanding health risk outcomes, and translating evidence into individualized approaches to therapy.

Sixth Annual Enhanced Recovery After Surgery Symposium highlights: work in progress or standard care?

Enhanced Recovery After Surgery (ERAS) protocols have demonstrated effectiveness in accelerating patient recovery and improving outcomes. Since the systemwide implementation of ERAS protocols at Baylor Scott & White Health, an annual multidisciplinary conference has provided a review of outcomes and advancements in the ERAS program. This meeting, coined the ERAS symposium, allows providers who utilize recovery protocols to collaborate with national and international leaders in the field to improve the clinical care of patients. The sixth annual ERAS symposium was held on February 10, 2023, and provided key presentations that discussed the latest results from ERAS efforts across multiple surgical specialties along with updates in anesthesia, nursing, and nutrition. A summary of those presentations, which included perioperative glycemic control, misconceptions in pain management, and emerging ERAS protocols in different surgical specialties, is provided to document the system progress.

General anesthesia with S-ketamine improves the early recovery and cognitive function in patients undergoing modified radical mastectomy: a prospective randomized controlled trial

BACKGROUND

Postoperative cognitive dysfunction (POCD) is a common postoperative disorder that is frequently observed after general anesthesia, which seriously threatens the quality of patients' life. Existing studies have demonstrated that S-ketamine plays an important role in improving neuroinflammation. This trial aimed to explore the effects of S-ketamine on quality of recovery and cognitive function in patients following modified radical mastectomy (MRM).

METHODS

Ninety patients aged 45 to 70 years with ASA grades of I or II, who underwent MRM, were selected. Patients were randomly assigned to the S-ketamine or control group. In the S-ketamine group, patients were induced with S-ketamine instead of sufentanil and maintained with S-ketamine and remifentanil. In the control group, patients were induced with sufentanil and maintained with remifentanil. The primary outcome was the Mini-Mental State Examination (MMSE) and Quality of Recovery-15 (QoR-15) score. Secondary outcomes including visual analog scale (VAS) score, cumulative propofol and opioids consumption, post anesthesia care unit (PACU) recovery time, occurrence of remedial analgesia, postoperative nausea and vomiting (PONV), other adverse events, as well as patient satisfaction.

RESULTS

The global QoR-15 scores at postoperative day 1 (POD1) were significantly higher in the S-ketamine group than in the control group (124 [119.5-128.0] vs. 119 [114.0-123.5], P = 0.002), with a median difference of 5 points (95% confidence interval [CI] [-8 to -2]). Similarly, the global QoR-15 scores at postoperative day 2 (POD2) in the S-ketamine group were significantly higher than in the control group (140.0 [133.0-145.0] vs. 132.0 [126.5-141.5], P = 0.004). In addition, among the five subcomponents of the 15-item scale, S-ketamine group had a higher score in terms of physical comfort, pain, and emotional state both at POD1 and POD2. In terms of MMSE score, S-ketamine could promote the recovery of postoperative cognitive function at POD1, but not at POD2. Furthermore, the consumption of opioids, VAS score, and remedial analgesia in the S-ketamine group decreased significantly.

CONCLUSIONS

Collectively, our findings support that general anesthesia with S-ketamine as a potential strategy showed high safety and could not only improve the quality of recovery mainly through improving pain, physical comfort, and emotional state but also promote the recovery of cognitive function on POD1 in patients undergoing MRM.

TRIAL REGISTRATION

The study was registered in the Chinese Clinical Trial Registry (registration No:ChiCTR2200057226, Date of registration: 04/03/2022).

Evaluating efficacy and safety of sub-anesthetic dose esketamine as an adjuvant to propofol/remifentanil analgosedation and spontaneous respiration for children flexible fibreoptic bronchoscopy: a prospective, double-blinded, randomized, and placebo-controlled clinical trial

Background: Flexible fiberoptic bronchoscopy (FFB) for children is widely performed under sedation. Currently, the optimal sedation regimen remains unclear. Esketamine is an N-methyl-D-aspartic acid (NMDA) receptor antagonist, which has stronger sedative and analgesic effects and exerts less cardiorespiratory depression than other sedatives. The purpose of this study was to evaluate whether a subanesthetic dose of esketamine as an adjuvant to propofol/remifentanil and spontaneous ventilation compared with control reduces the procedural and anesthesia-related complications of FFB in children. Materials and methods: Seventy-two children ≤ 12 years of age who were scheduled for FFB were randomly assigned, in a 1:1 ratio, to the esketamine-propofol/remifentanil (Group S, n = 36) or to the propofol/remifentanil group (Group C, n = 36). All children were retained spontaneous ventilation. The primary outcome was the incidence of oxygen desaturation (respiratory depression). Perioperative hemodynamic variables, blood oxygen saturation (SPO₂), end-tidal partial pressure of carbon dioxide (PetCO₂), respiratory rate (R), and the Bispectral index (BIS), induction time, procedural time, recovery time, the time to the ward from the recovery room, consumption of propofol and remifentanil during the procedure and the appearance of adverse events, including paradoxical agitation following midazolam administration, injection pain, laryngospasm, bronchospasm, PONV, vertigo, and hallucination were also compared. Results: The incidence of oxygen desaturation was significantly lower in Group S (8.3%) compared to Group C (36.1%, p = 0.005). The perioperative hemodynamic profile including SBP, DBP, and HR were more stable in Group S than that in Group C (p < 0.05). Consumption of propofol and remifentanil was lower in Group S than in Group C (p < 0.05). Furthermore, PAED scores, cough scores and injection pain were lower in the Group S than in Group C (p < 0.05). The recovery time of Group S was slightly longer than that of Group C (p < 0.05). Nobody happened paradoxical agitation following midazolam administration, PONV, vertigo, and hallucinations in both groups (p > 0.05). Conclusion: Our findings indicate that a subanesthetic dose of esketamine as an adjuvant to propofol/remifentanil and spontaneous respiration is an effective regimen for children undergoing FFB. Our findings will provide a reference for clinical sedation practice during these procedures in children. Clinical Trail Registration: Chinese clinicaltrials.gov registry (identifier: ChiCTR2100053302).

A prospective observational study of the efficacy of ketamine for rescue analgesia in the postanesthesia recovery unit

BACKGROUND

Early severe postoperative pain is frequently resistant to management with opioid analgesia alone. Perioperative low-dose ketamine as an analgesia adjunct has been studied extensively. Its efficacy as a rescue analgesic in the postanesthesia care unit (PACU) has not been determined. The objective of this study was to evaluate the analgesic efficacy of low-dose bolus ketamine for opioid-resistant pain in the PACU by measuring its effect on numerical rating scale (NRS) pain scores and opioid requirement.

METHODS

This was a prospective observational study of adult noncardiac surgery patients with significant postoperative pain in the PACU. Patients were administered bolus doses of intravenous ketamine in 10-mg increments, repeated two to three times to an approximate maximum dose of 0.25 mg·kg-1. Primary outcomes were resting pain score reduction and opioid use from time of bolus ketamine administration to 30 min after administration of final ketamine bolus. The secondary outcome was incidence of side effects from ketamine administration.

RESULTS

A convenience sample of 100 patients was chosen. The mean (standard deviation) NRS resting pain score reduction 30 min after iv ketamine administration was 2.7 (1.8) (P < 0.001). Patients with a history of previous opioid use or chronic pain were not more responsive to the effects of low-dose bolus ketamine. There were no ketamine-related adverse effects in any of the study patients.

CONCLUSION

Administration of low-dose bolus ketamine in the PACU for severe opioid-resistant pain was associated with a significant improvement in analgesia in this observational study.

Prenatal Exposure to General Anesthesia Drug Esketamine Impaired Neurobehavior in Offspring

Prenatal exposure to anesthetics has raised increasing attention about the neuronal development in offspring. Animal models are usually used for investigation. As a new drug, esketamine is the s-isoform of ketamine and is twice as potent as the racemic ketamine with less reported adverse effects. Esketamine is currently being used and become more favorable in clinical anesthesia work, including surgeries during pregnancy, yet the effect on the offspring is unknown. The present study aimed to elucidate the effects of gestational administration of esketamine on neuronal development in offspring, using a rat model. Gestational day 14.5 pregnant rats received intravenous injections of esketamine. The postnatal day 0 (P0) hippocampus was digested and cultured in vitro to display the neuronal growth morphology. On Day 4 the in vitro experiments revealed a shorter axon length and fewer dendrite branches in the esketamine group. The results from the EdU- imaging kit showed decreased proliferative capacity in the subventricular zone (SVZ) and dentate gyrus (DG) in both P0 and P30 offspring brains in the esketamine group. Moreover, neurogenesis, neuron maturity and spine density were impaired, resulting in attenuated long-term potentiation (LTP). Compromised hippocampal function accounted for the deficits in neuronal cognition, memory and emotion. The evidence obtained suggests that the neurobehavioral deficit due to prenatal exposure to esketamine may be related to the decrease phosphorylation of CREB and abnormalities in N-methyl-D-aspartic acid receptor subunits. Taken together, these results demonstrate the negative effect of prenatal esketamine exposure on neuronal development in offspring rats. G14.5 esketamine administration influenced the neurobehavior of the offspring in adolescence. Poorer neuronal growth and reduced brain proliferative capacity in late gestation and juvenile pups resulted in impaired P30 neuronal plasticity and synaptic spines as well as abnormalities in NMDAR subunits. Attenuated LTP reflected compromised hippocampal function, as confirmed by behavioral tests of cognition, memory and emotions. This figure was completed on the website of Figdraw.

Treatment of Acute Pain in Patients on Naltrexone: A Narrative Review

PURPOSE OF REVIEW

The tissue damage and trauma associated with surgery almost always result in acute postoperative pain. The intensity of postoperative pain can range from mild to severe. Naltrexone is suitable for patients who do not wish to be on an agonist treatment such as methadone or buprenorphine. However, naltrexone has been shown to complicate postoperative pain management.

RECENT FINDINGS

Multiple studies have found that the use of naltrexone can increase the opioid requirement for postoperative pain control. Other modalities exist that can help outside of opioids such as ketamine, lidocaine/bupivacaine, duloxetine, and non-pharmacological management can help manage pain. Multimodal pain regiments should also be employed in patients. In addition to traditional methods for postoperative pain management, other methods of acute pain control exist that can help mitigate opioid dependence and help control pain in patients who use naltrexone for their substance use disorders.

Perioperative use of ketamine infusion versus dexmedetomidine infusion for analgesia in obese patients undergoing bariatric surgery: a double-blinded three-armed randomized controlled trial

BACKGROUND

Bariatric surgery depends on the development of novel anesthetic techniques to reduce the incidence of complications and improve postoperative outcomes. Ketamine and dexmedetomidine have been used for perioperative analgesia and we hypothesized that they would decrease postoperative morphine requirements. The objective of this trial is to study whether choice of ketamine or dexmedetomidine infusion would affect postoperative total morphine consumption.

METHODS

Ninety patients were equally randomized into three groups. The ketamine group received a bolus dose (0.3 mg/kg) of ketamine over 10 min, followed by an infusion of the same drug (0.3 mg/kg/h). The dexmedetomidine group received a bolus dose (0.5 mcg/kg) of dexmedetomidine over 10 min, followed by an infusion of this drug (0.5 mg/kg/h). The control group received a saline infusion. All infusions were given till 10 min before the end of surgeries. Intraoperative fentanyl was given when patient developed hypertension and tachycardia despite adequate anesthesia and muscle relaxation. Postoperative pain was managed by a rescue dose of 4 mg of IV morphine, with a minimum interval of 6 h between morphine doses if the numerical rating scale (NRS) score was ≥ 4. The primary outcome was the total morphine dose, and the secondary outcomes were intraoperative fentanyl requirement, time to extubation, postoperative nausea and vomiting (PONV), NRS scores, and modified observer's agitation/sedation scale (MOASS) scores.

RESULTS

Compared with ketamine, dexmedetomidine decreased the need for fentanyl intraoperatively (160 ± 42 µg), shortened the time to extubation (3 ± 1 min), and improved MOASS and PONV scores. In turn, ketamine decreased postoperative NRS scores and the need for morphine (3 ± 3 mg).

CONCLUSIONS

Dexmedetomidine treatment was associated with lower fentanyl doses, a shorter time to extubation, and better MOASS and PONV scores. Ketamine treatment was associated with significantly lower NRS scores and morphine doses. These results indicated that dexmedetomidine effectively decreased intraoperative fentanyl requirement and the time to extubation, while ketamine decreased the need for morphine.

TRIAL REGISTRATION

This trail was registered on the clinicaltrials.gov registry (NCT04576975) on October 6, 2020.

Subanaesthetic single-dose ketamine as an adjunct to opioid analgesics for acute pain management in the emergency department: a systematic review and meta-analysis

OBJECTIVE

To evaluate the effectiveness of a subanaesthetic single-dose ketamine (SDK) as an adjunct to opioids for acute pain in emergency department (ED) settings.

DESIGN

Systematic review and meta-analysis.

METHODS

A systematic search was performed in MEDLINE, Embase, Scopus and Web of Science through March 2022. Randomised controlled trials (RCTs) that investigated SDK as an adjunct to opioids in adult patients for any painful condition in ED settings were selected. Two reviewers screened studies, extracted data and assessed study quality. Data were pooled using random-effects models. The primary outcome was mean pain intensity score measured at baseline, >0-15 min, >15-30 min, >30-45 min, 60 min, 90 min and 120 min. Secondary outcomes included need for rescue analgesia, adverse events and patient satisfaction. Results were reported as mean differences (MDs) and risk ratios. Statistical heterogeneity was calculated using the I ² statistic.

RESULTS

Eight RCTs were included (n=903). Studies were judged to be at moderate to high risk of bias. Mean pain intensity scores were significantly lower 60 min after study drug administration favouring adjuvant SDK (MD -0.76; 95% CI -1.19 to -0.33), compared with opioids alone. There was no evidence of differences in mean pain intensity scores at any other time point. Patients who received adjuvant SDK were less likely to require rescue analgesia, no more likely to experience serious side effects and had higher satisfaction scores, compared with opioids alone.

CONCLUSIONS

Available evidence suggests adjuvant SDK can have an effect on lowering pain intensity scores. Although reduction of pain scores was not clinically significant, the combination of reduced pain intensity and reduced opioid requirements suggest the results could be clinically important and support the potential utility of SDK as an adjunct to opioids to treat acute pain in adult ED patients. However, current evidence is limited and higher quality RCTs are needed.

PROSPERO REGISTRATION NUMBER

CRD42021276708.

Efficacy of Lidocaine Infusion in High-Risk Vascular Surgery—A Randomized, Double-Blind, Placebo-Controlled Single-Center Clinical Trial

Background: In perioperative pain control, adjuvants such as lidocaine can reduce opioid consumption in a specific type of surgery. The aim of this single-center prospective double-blinded randomized controlled trial was to determine opioid consumption in the perioperative period in patients receiving continuous lidocaine infusion. Methods: Patients undergoing elective abdominal aorta and/or iliac arteries open surgery were randomized into two groups to receive 1% lidocaine or placebo at the same infusion rate based on ideal body weight (bolus of 0.15 mL/kg during the induction of anesthesia followed by continuous infusion of 0.2 mL/kg/h during surgery; postoperatively 0.1 mL/kg/h for 24 h) additionally to standard opioid analgesia. Results: Total opioid consumption within 24 h after surgery was 89.2 mg (95%CI 80.9–97.4) in the lidocaine and 113.1 mg (95%CI 102.5–123.6) in the placebo group (p = 0.0007). Similar findings were observed in opioid consumption intraoperatively (26.7 mg (95%CI 22.2–31.3) vs. 35.1 mg (95%CI 29.1–41.2), respectively, p = 0.029) and six hours postoperatively (47.5 mg (IQR 37.5–59.5) vs. 60 mg (IQR 44–83), respectively, p = 0.01). Conclusions: In high-risk vascular surgery, lidocaine infusion as an adjunct to standard perioperative analgesia is effective. It may decrease opioid consumption by more than 20% during the first 24 h after surgery, with no serious adverse effects noted during the study period.

S110-Opioid-free analgesia after outpatient general surgery: A qualitative study focused on the perspectives of patients and clinicians involved in a pilot trial

BACKGROUND

Opioid-free analgesia (OFA) may mitigate opioid-related harms after outpatient general surgery; however, the comparative effectiveness of this approach should be assessed in robust randomized controlled trials (RCTs). Undertaking an RCT on OFA raises important practical concerns, including surgeon and patient hesitation regarding pain management without opioids. We conducted a qualitative study to explore patients' and clinicians' perspectives and experiences with a pilot trial focused on OFA after outpatient general surgery.

METHODS

Patients undergoing outpatient abdominal and breast procedures were randomized to receive post-discharge opioid analgesia (OA) or OFA. Semi-structured interviews with patients and clinicians involved in the trial were conducted to elicit personal perspectives and experiences. Purposive sampling for maximum variation was used to recruit participants with diverse characteristics. Transcribed interviews were assessed using inductive thematic analysis.

RESULTS

Ten patients (5 abdominal, 5 breast) and 10 clinicians (6 surgeons, 2 anesthesiologists, 2 nurses) were interviewed. Five major themes emerged: readiness for trial engagement, pre-trial thoughts about the interventions, postoperative pain experiences, intervention acceptability, and trial refinement. Most patients were open to OFA. Clinicians expressed willingness to prescribe OFA, particularly after less invasive procedures and when using peripheral nerve blocks (PNBs). Concerns were raised regarding the adequacy of pain control and side effects of non-opioid drugs (e.g., NSAID-induced bleeding, kidney injury). Overall, participants were enthusiastic about the trial and recognized its relevance; clinicians praised the study design and organization; and patients valued the use of electronic questionnaires. Suggestions for improvements included preventing potential bias arising from the use of PNBs (i.e., via standardization or stratification) and reducing patient burden (i.e., decreasing postoperative questionnaires).

CONCLUSION

Patients and clinicians who participated in a pilot RCT generally accept the clinical equipoise between OA versus OFA after outpatient general surgery and recognize the need for methodologically robust trials to inform evidence-based analgesia prescribing.

Intraoperative pharmacologic opioid minimisation strategies and patient-centred outcomes after surgery: a scoping review protocol

INTRODUCTION

For close to a century opioid administration has been a standard of care to complement anaesthesia during surgery. Considering the worldwide opioid epidemic, this practice is now being challenged and there is a growing use of systemic pharmacological opioid minimising strategies. Our aim is to conduct a scoping review that will examine clinical trials that have evaluated the impact of intraoperative opioid minimisation strategies on patient-centred outcomes and identify promising strategies.

METHODS AND ANALYSIS

Our scoping review will follow the framework developed by Arksey and O'Malley. We will search MEDLINE, Embase, CENTRAL, Web of Science and CINAHL from their inception approximately in March 2023. We will include randomised controlled trials, assessing the impact of systemic intraoperative pharmacologic opioid minimisation strategies on patient-centred outcomes. We define an opioid minimisation strategy as any non-opioid drug with antinociceptive properties administered during the intraoperative period. Patient-centred outcomes will be defined and classified based on the consensus definitions established by the Standardised Endpoints in Perioperative Medicine initiative (StEP-COMPAC group) and informed by knowledge users and patient partners. We will use a coproduction approach involving interested parties. Our multidisciplinary team includes knowledge users, patient partners, methodologists and knowledge user organisations. Knowledge users will provide input on methods, outcomes, clinical significance of findings, implementation and feasibility. Patient partners will participate in assessing the relevance of our design, methods and outcomes and help to facilitate evidence translation. We will provide a thorough description of available clinical trials, compare their reported patient-centred outcome measures with established recommendations and identify promising strategies.

ETHICS AND DISSEMINATION

Ethics approval is not required for the review. Our scoping review will inform future research including clinical trials and systematic reviews through identification of important intraoperative interventions. Results will be disseminated through a peer-reviewed publication, presentation at conferences and through our network of knowledge user collaborators.

REGISTRATION

Open Science Foundation (currently embargoed).

Esketamine combined with pregabalin on acute postoperative pain in patients undergoing resection of spinal neoplasms: study protocol for a randomized controlled trial

BACKGROUND

Perioperative pain management is one of the most challenging issues for patients with spinal neoplasms. Inadequate postoperative analgesia usually leads to severe postsurgical pain, which could cause patients to suffer from many other related complications. Meanwhile, there is no appropriate analgesic strategy for patients with spinal neoplasms.

METHODS/DESIGN

This is a protocol for a randomized double-blind controlled trial to evaluate the effect of esketamine combined with pregabalin on postsurgical pain in spinal surgery. Patients aged 18 to 65 years scheduled for spinal neoplasm resection will be randomly allocated into the combined and control groups in a 1:1 ratio. In the combined group, esketamine will be given during the during the surgery procedure until 48-h postoperative period, and pregabalin will be taken from 2 h before the surgery to 2 weeks postoperatively. The control group will receive normal saline and placebo capsules at the same time points. Both groups received a background analgesic regimen by using patient-controlled intravenous analgesia (containing 100 μg sufentanil and 16 mg ondansetron) until 2 days after surgery. To ensure the accuracy and reliability of this trial, all the researchers and patients will be blinded until the completion of this study. The primary outcome will be the proportion of patients with acute moderate-to-severe postsurgical pain (visual analog scale, VAS ≥ 40, range: 0-100, with 0, no pain; 100, the worst pain) during the 48-h postoperative period. The secondary outcomes will include the maximal VAS scores (when the patients felt the most intense pain over the last 24 h before being interviewed) at 0-2 h, 2-24 h, 24-48 h, and 48-72 h after leaving the operating room and 24 h before discharge; the incidence of acute moderate-to-severe postsurgical pain at each other time point; chronic postsurgical pain assessment; neuropathic pain assessment; and the incidence of drug-related adverse events and other postoperative complications, such as postoperative delirium and postoperative nausea and vomiting (PONV).

DISCUSSION

The aim of this study was to evaluate the effect of esketamine combined with pregabalin on acute postsurgical pain in patients undergoing resection of spinal neoplasms. The safety of this perioperative pain management strategy will also be examined.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05096468. Registered on October 27, 2021.

Postoperative Analgesia in Enhanced Recovery After Surgery Protocols: Trends and Updates

Multimodal analgesia is an effective strategy to decrease opioid use after surgery and has been a mainstay of the surgical contribution to combat the opioid epidemic. Postoperative multimodal analgesia in Enhanced Recovery After Surgery (ERAS) continues to evolve as different adjuncts are added and removed based on the most up to date literature. This review examines recent trends in ERAS analgesia and what current evidence and research supports as well as those adjuncts that may not be as beneficial as once thought.

Utilization of Ketamine in Total Knee and Hip Joint Arthroplasty: An Evidence-Based Review

PURPOSE

To evaluate the efficacy of ketamine in total knee and hip arthroplasty.

DESIGN

Evidence-based review.

METHODS

Following the guidelines outlined in the PRISMA statement, a comprehensive search was conducted using Google Scholar, PubMed, CINAHL, Cochrane Collaboration, and other grey literature. Only randomized controlled studies and pre-appraised evidence such as systematic review and meta-analysis examining the effects of ketamine in total knee and hip arthroplasty were included. The quality appraisal of the literature was conducted using the proposed algorithm described in the Johns Hopkins Nursing Evidence-Based Practice Evidence Level and Quality Guide.

FINDINGS

Three systematic reviews and meta-analyses and 2 randomized controlled trials involving 1284 patients were included in this review. The use of ketamine reduced pain scores within the 24 hours after surgery. In addition, evidence suggests that patients who were treated with ketamine consumed fewer opioids 24 and 48 hours after surgery. Furthermore, ketamine reduced the incidence of postoperative nausea and vomiting with no effects on the incidence of hallucinations and central nervous system side effects. All studies included in the review were categorized as Level I and rated Grade A implying strong confidence in the true effects of ketamine in all outcome measures in the review.

CONCLUSIONS

The current evidence demonstrates the viability of ketamine as a safe and effective alternative to opioids in the perioperative setting with major total joint arthroplasty surgery. Decreased pain scores and opioid consumption up to 48 hours into the postoperative period were observed in a number of the appraised articles.

Impact of Ketamine on Quality of Recovery after Laparoscopic Surgery: A Single-Centre Single-Blinded Trial Using the QoR-15 Questionnaire

Background

The quality of recovery is a cluster of patient-related outcomes that emphasise not only pain but different physical and emotional dimensions. Traditionally, ketamine is used to improve postoperative analgesia and avoid opioid consumption and opioid-related side effects.

Objective

The present study sought to evaluate if intraoperative ketamine administration (as a part of multimodal analgesia) influences the quality of recovery after laparoscopic surgery.

Design

A prospective two-armed, single-blinded trial. Settings. Tertiary single-centre trial between July 2021 and January 2022. Patients. From the 146 patients initially admitted to the study, 127 patients were enrolled, 60 in the ketamine group (group K) and 67 in the control group (group NK). Intervention. Both groups received a rigid intraoperative anaesthesia protocol; furthermore, in group K, 0.5 mg/kg of the ideal body weight of ketamine was administered. Main Outcome Measures. The primary outcome was to evaluate the effect of ketamine administration on the postoperative quality of recovery using the Portuguese version of the Quality of Recovery-15 (QoR-15) Questionnaire 24 h after surgery. The total score and minimal clinically significant difference (MCID) of the QoR-15 were compared. Other variables were also assessed such as the presence of emergence delirium (ED), the Numeric Rating Scale (NRS) for pain, and the presence of postoperative nausea and vomiting (PONV).

Results

A total of 127 patients were allocated to the study groups, 60 in group K and 67 in group NK. Regarding the primary outcome, no differences were found in individual categories (15 items) and in the total score of QoR-15 (p=0.214). Concerning improvement (MCID ≥ 8) or worsening (MCID ≤ 8) in quality of recovery, no difference was found between the groups (24 vs. 32 and 6 vs. 6; p=0.776). Finally, no difference was found in secondary postoperative outcomes including ED (p=0.55), NRS (p=0.401), and PONV (p=0.55).

Conclusion

In this study, the administration of ketamine in laparoscopic surgery had no impact on the quality of recovery 24 h after surgery. This trial is registered with NCT03724019.

Evaluating the Influence of IV Ketamine on Postoperative Opioid Use for Surgical Patients at a Tertiary Care Centre

Background

Subanesthetic doses of ketamine have been shown to improve the efficacy of opioids, increase pain control, and exemplify opioid-sparing effects when used as postoperative analgesia for adults.

Objectives

To determine, for surgical patients, the impact of IV ketamine infusions on opioid use in hospital, overall and within 24 h before discharge, as well as pain scores.

Methods

A retrospective matched cohort study was conducted, in which surgical patients exposed to ketamine were compared with those not exposed to ketamine, among admissions from January 1, 2018, to February 28, 2020. Patients were matched for age, surgical service, and sex.

Results

A total of 104 patients were included in the study. Overall, there was no significant difference in mean total opioid use in hospital for patients exposed and not exposed to ketamine (171.7 mg versus 115.5 mg oral morphine equivalent [OME], p = 0.09), nor was there any difference in opioid use in the 24 h before discharge (28.2 mg versus 18.2 mg OME, p = 0.14). Patient-reported pain scores did not differ between groups. More patients in the ketamine group experienced hallucinations than in the group not exposed to ketamine (5 versus 0, p = 0.024).

Conclusions

Overall, subanesthetic doses of IV ketamine used postoperatively in surgical patients did not decrease opioid use or patient-reported pain. More patients who received ketamine had documented hallucinations. These results will help guide postoperative analgesia practice and strategies to reduce opioid use.

Effects of esketamine on postoperative rebound pain in patients undergoing unilateral total knee arthroplasty: a single-center, randomized, double-blind, placebo-controlled trial protocol

Introduction

Rebound pain, transient and acute postoperative pain after the disappearance of regional block anesthesia, has been a concern in recent years. Insufficient preemptive analgesia and hyperalgesia induced by regional block are the main mechanisms. At present, the evidence for the treatment of rebound pain is limited. The esketamine, as an antagonist of the N-methyl-D-aspartate receptor, has been proven to prevent hyperalgesia. Therefore, this trial aims to evaluate the impact of esketamine on postoperative rebound pain in patients undergoing total knee arthroplasty.

Methods/design

This study is a single-center, prospective, double-blind, randomized, placebo-controlled trial. Participants who plan to undergo total knee arthroplasty will be randomly assigned to the esketamine group (N = 178) and placebo group (N = 178) in a ratio of 1:1. This trial aims to evaluate the impact of esketamine on postoperative rebound pain in patients undergoing total knee arthroplasty. The primary outcome of this trial is the incidence of rebound pain within 12 h after the operation in the esketamine group and the placebo group. The secondary outcome will be to compare (1) the incidence of rebound pain 24 h after the operation; (2) the time to enter the pain cycle for the first time within 24 h after the procedure; (3) the first time of rebound pain occurred within 24 h after surgery; (4) the modified rebound pain score; (5) NRS score under rest and exercise at different time points; (6) the cumulative opioid consumption at different time points; (7) patient's prognosis and knee joint function evaluation; (8) blood glucose and cortisol concentration; (9) patient's satisfaction score; (10) adverse reactions and adverse events.

Discussion

The effect of ketamine on preventing postoperative rebound pain is contradictory and uncertain. The affinity of esketamine to the N-methyl-D-aspartate receptor is about four times higher than levo-ketamine, the analgesic effect is 3 times higher than levo-ketamine, and there are fewer adverse mental reactions. To our knowledge, there is no randomized controlled trial to verify the impact of esketamine on postoperative rebound pain in patients undergoing total knee arthroplasty. Therefore, this trial is expected to fill an important gap in relevant fields and provide novel evidence for individualized pain management.

Clinical Trial Registration

http://www.chictr.org.cn, identifier ChiCTR2300069044.

S-Ketamine attenuates inflammatory effect and modulates the immune response in patients undergoing modified radical mastectomy: A prospective randomized controlled trial

Objective: This study aimed to investigate the impact of varying dosages of S-ketamine on perioperative immune-inflammatory responses in patients undergoing modified radical mastectomy (MRM). Methods: This is a prospective, randomized, controlled trial. A total of 136 patients with American Society of Anesthesiologists status I/II scheduled for MRM were enrolled and randomly assigned into groups to receive the control (C) or one of three different doses [0.25 (L-Sk), 0.5 (M-Sk), or 0.75 (H-Sk) mg/kg] of S-ketamine. The primary outcomes were the cellular immune function and inflammatory factors before anesthesia and at the end of (T1) and 24 h (T2) after the surgery. Secondary outcomes included the visual analog scale (VAS) score, opioid consumption, rate of remedial analgesia, adverse events, and patient satisfaction. Results: The percentage and absolute counts of CD3⁺ and CD4⁺ cells in groups L-Sk, M-Sk, and H-Sk were higher than those of group C at T1 and T2. Moreover, a pairwise comparison revealed that the percentage in group H-Sk was higher than those in the L-Sk and M-Sk groups (p < 0.05). The ratio of CD4⁺/CD8⁺ was lower in group C at T1 and T2 than those in groups M-Sk and H-Sk (p < 0.05). There was no significant difference in the percentage and absolute counts of natural killer (NK) cells and B lymphocytes among the four groups. However, compared with group C, the concentrations of white blood cells (WBC), neutrophils (NEUT), hypersensitive C-reactive protein (hs-CRP), the neutrophil-to-lymphocyte ratio (NLR), systemic inflammation response index (SIRI), and systemic immune-inflammation index (SII) at T1 and T2 in three different doses of S-ketamine groups were significantly low, and the lymphocytes were significantly high. The ratio of SIRI and NLR at T2 in group M-Sk was lower than that in group L-Sk (p < 0.05). Additionally, a significant decrease in VAS score, opioid consumption, rates of remedial analgesia, and adverse events was observed in the M-Sk and H-Sk groups. Conclusion: Collectively, our study demonstrates that S-ketamine could reduce opioid consumption, decrease postoperative pain intensity, exert a systemic anti-inflammatory effect, and attenuate immunosuppression in patients undergoing MRM. Moreover, we found that the effects of S-ketamine are related to the dose used, with significant differences observed in 0.5 or 0.75 mg/kg of S-ketamine. Clinical Trial Registration: chictr.org.cn, identifier ChiCTR2200057226.

Single-Dose of Postoperative Ketamine for Postoperative Pain After Mastectomy: A Pilot Randomized Controlled Trial

Background and Objectives

Perioperative ketamine has been shown to reduce opioid consumption and pain after surgery. Ketamine is most often given as an infusion, but an alternative is single-dose ketamine. Single-dose ketamine at up to 1 mg/kg has been shown to reduce symptoms of depression, and a wide range of dosages has been used for pain in the emergency department. However, limited data exists on the tolerability and efficacy of a single-dose of ketamine at 0.6 mg/kg for pain when administered immediately after surgery. We conducted a pilot study of single-dose ketamine in patients undergoing mastectomy with reconstruction, hypothesizing that a single-dose of ketamine is well tolerated and can relieve postoperative pain and improve mood and recovery.

Methods

This is a randomized, single-blind, placebo-controlled, two-arm parallel, single-center study. Thirty adult women undergoing mastectomy with reconstruction for oncologic indication received a single-dose of ketamine (0.6mg/kg) or placebo after surgery in the post-anesthesia care unit (PACU). Patients were followed through postoperative day (POD) 7. The primary outcome was postoperative pain measured by the Brief Pain Inventory (BPI) pain subscale on POD 1 and 2. Secondary outcomes include effects on opioid use, PROMIS fatigue and sleep, mood, Quality of Recovery-15, and the Breast Cancer Pain Questionnaire.

Results

Side effects were minor and not significantly different in frequency between groups. The ketamine group reported lower scores on the BPI pain severity subscale, especially at POD 7; however, the difference was not statistically significant. There were no statistically significant differences between ketamine and placebo groups for the secondary outcomes.

Conclusion

A single-dose of ketamine at 0.6mg/kg administered postoperatively in the PACU is well tolerated in women undergoing mastectomy and may confer better pain control up to one week after surgery. Future studies with larger sample sizes are necessary to adequately characterize the effect of postoperative single-dose ketamine on pain control in this population.

Effects of the Different Doses of Esketamine on Postoperative Quality of Recovery in Patients Undergoing Modified Radical Mastectomy: A Randomized, Double-Blind, Controlled Trial

Purpose

This study aims to investigate the effects of the different doses of esketamine on postoperative quality of recovery in patients undergoing modified radical mastectomy.

Methods

Ninety-nine female patients were randomly allocated to three groups: the low-dose esketamine group (group E₁) (0.5 mg/kg loading, 2 µg/kg/h infusion), the high-dose esketamine group (group E₂) (0.5 mg/kg loading, 4 µg/kg/h infusion), the control group (group C) (received normal saline). The primary outcome was the quality of recovery-15 (QoR-15) scores on postoperative day 1 (POD1) and days 3 (POD3). The secondary outcomes were the sleep quality scores on POD1, bispectral index (BIS) value at 10, 30, and 60 min after operation, numeric rating scale (NRS) pain scores within 24 h after surgery, nausea, vomiting, drowsiness, nightmare, and intraoperative awareness.

Results

The total QoR-15 scores were higher in group E₁ and group E₂ than in group C on POD1 and POD3 (P<0.05). The sleep quality scores on POD1 and BIS value at 10, 30, and 60 min after operation were higher in group E₁ and group E₂ than in group C (P<0.05). The NRS pain scores at 2, 4 and 6 h after surgery in group E₁ and at 2, 4, 6, 12 and 24 h after surgery in group E₂ were lower than in group C (P<0.05). The NRS pain scores at 6, 12 and 24 h after surgery in group E₂ were lower than in group E₁ (P<0.05). The incidence of drowsiness was higher in group E₁ and group E₂ than in group C (P<0.05).

Conclusion

Esketamine infusion improved to some extent the quality of recovery on POD1 and POD3 in patients undergoing modified radical mastectomy, especially 4 µg/kg/h esketamine was better, but the BIS value and incidence of drowsiness were significantly increased.

Transversus abdominis plane (TAP) blocks for prevention of postoperative pain in women undergoing laparoscopic and robotic gynaecological surgery

This is a protocol for a Cochrane Review (intervention). The objectives are as follows:

To evaluate the benefits and harms of TAP blocks for the prevention of postoperative pain in women undergoing laparoscopic and robotic gynaecological surgery compared to no block, sham block, or injection of local anaesthetic. 

Knowing the Enemy Is Halfway towards Victory: A Scoping Review on Opioid-Induced Hyperalgesia

Opioid-induced hyperalgesia (OIH) is a paradoxical effect of opioids that is not consensually recognized in clinical settings. We conducted a revision of clinical and preclinical studies and discuss them side by side to provide an updated and renewed view on OIH. We critically analyze data on the human manifestations of OIH in the context of chronic and post-operative pain. We also discuss how, in the context of cancer pain, though there are no direct evidence of OIH, several inherent conditions to the tumor and chemotherapy provide a substrate for the development of OIH. The review of the clinical data, namely in what concerns the strategies to counter OIH, emphasizes how much OIH rely mechanistically on the existence of µ-opioid receptor (MOR) signaling through opposite, inhibitory/antinociceptive and excitatory/pronociceptive, pathways. The rationale for the maladaptive excitatory signaling of opioids is provided by the emerging growing information on the functional role of alternative splicing and heteromerization of MOR. The crossroads between opioids and neuroinflammation also play a major role in OIH. The latest pre-clinical data in this field brings new insights to new and promising therapeutic targets to address OIH. In conclusion, although OIH remains insufficiently recognized in clinical practice, the appropriate diagnosis can turn it into a treatable pain disorder. Therefore, in times of scarce alternatives to opioids to treat pain, mainly unmanageable chronic pain, increased knowledge and recognition of OIH, likely represent the first steps towards safer and efficient use of opioids as analgesics.

Ultrasound-guided posterior quadratus lumborum block can reduce postoperative opioid consumption and promote rapid recovery in patients undergoing sutureless laparoscopic partial nephrectomy: A triple-blind, randomized, controlled study

Purpose

We hypothesized that posterior quadratus lumborum block would reduce postoperative opioid consumption and improve the quality of recovery in patients undergoing sutureless laparoscopic partial nephrectomy.

Materials and methods

The study included 60 patients, ages 18−65 with American Society of Anesthesiologists scores of I-II scheduled for elective sutureless laparoscopic partial nephrectomy. Before general anesthesia, 60 participating patients were randomly allocated to receive a 30-ml injection posterior to the quadratus lumborum muscle with either 0.375% ropivacaine (n = 30) or normal saline (n = 30). The primary outcomes included cumulative opioid consumption within 12 h postoperatively and quality of postoperative recovery at 48 h. Secondary outcomes included the Numerical Rating Scale (NRS), opioid consumption by period, first time to press the analgesic pump, number of patients needing rescue analgesia, blood glucose and cortisol concentrations, early postoperative recovery indicators, and adverse events.

Results

There were 48 patients included in the final analysis. The intervention group had lower cumulative consumption of sufentanil within 12 h postoperatively and higher quality of postoperative recovery scores at 48 h postoperatively compared with the control group (p < 0.001). The NRS at resting and movement of the intervention group was lower at 0 h, 6 h, and 12 h after surgery than in the control group (p < 0.05). At prespecified intervals (0 to 2 h, 2 to 6 h, 6 to 12 h, 12 to 24 h, and 24 to 48 h) after surgery, the intervention group had lower consumption of sufentanil compared with the control group (p < 0.05). The intervention group took longer to press the analgesic pump for the first time within 48 h after surgery compared with the control group (p < 0.001). The postoperative blood glucose and cortisol concentrations in the intervention group were lower than in the control group (p < 0.05). The times to first excretion, ambulation, and discharge were shorter in the intervention group compared with the control group (p < 0.05). There was no significant difference in adverse events between the two groups.

Conclusions

Our trial demonstrated that patients who received posterior quadratus lumborum block had significantly lower opioid consumption within 12 h postoperatively and had a better quality of recovery at 48 h postoperatively. Therefore, we recommend posterior quadratus lumborum block as an option for postoperative analgesia in patients undergoing sutureless laparoscopic partial nephrectomy.

Trial Registration

http://www.chictr.org.cn, identifier ChiCTR2100053439.

Effective anesthetic management with remimazolam and ketamine without muscle relaxants for parotidectomy in a patient with myotonic dystrophy: A case report

RATIONALE

Patients with myotonic dystrophy (DM) are highly sensitive to anesthetics, muscle relaxants, and opioids, necessitating appropriate anesthetic management. Recently, remimazolam, an ultra-short-acting benzodiazepine, has been approved for use as a general anesthetic in Japan, and patients with DM have reportedly been treated with remimazolam. However, to the best of our knowledge, no study has reported on endotracheal intubation without the use of muscle relaxants under anesthetic management with remimazolam, nor on the combination of remimazolam and ketamine.

PATIENT CONCERNS

A 23-year-old man was referred to our hospital for right parotidectomy and diagnosed with DM just before surgery. At the surgeon's discretion, he was scheduled to undergo nerve monitoring to preserve the facial nerve.

DIAGNOSIS

Myotonic dystrophy.

INTERVENTIONS

We planned total intravenous anesthesia without muscle relaxants and selected remimazolam for anesthesia. Our aim was to prevent the intraoperative or postoperative complications associated with propofol and inhalational anesthetics. Additionally, we selected multimodal analgesia, including ketamine, to avoid opioid use. General anesthesia was induced with ketamine 30 mg, remifentanil 0.72 μg/kg/min, and remimazolam 12 + 6 mg. Endotracheal intubation was performed under videolaryngoscopy without the use of muscle relaxants. For postoperative analgesia, we administered additional doses of ketamine 20 mg and acetaminophen 1000 mg, and the surgeons infiltrated 8 mL of xylocaine 0.5% with epinephrine into the skin incision before starting the surgery. Intraoperative anesthesia was maintained with remimazolam 0.9 to 1.0 mg/kg/h and remifentanil 0.26 to 0.50 μg/kg/min. Flumazenil was administered for rapid awakening and safe extubation. All vitals, including the bispectral index, were stable during surgery.

OUTCOMES

The patient did not develop facial nerve paralysis, sore throat, or hoarseness, nor did he have any memory of the surgery. Good postoperative analgesia was achieved.

LESSONS

We achieved effective anesthetic management using remimazolam without muscle relaxants in a patient with DM. Furthermore, the combination of remimazolam and ketamine provided good sedation and postoperative analgesia.

Elective surgery in ankle and foot disorders-best practices for management of pain: a guideline for clinicians

PURPOSE

Complex elective foot and ankle surgeries are often associated with severe pain pre- and postoperatively. When inadequately managed, chronic postsurgical pain and long-term opioid use can result. As no standards currently exist, we aimed to develop best practice pain management guidelines.

METHODS

A local steering committee (n = 16) surveyed 116 North American foot and ankle surgeons to understand the "current state" of practice. A multidisciplinary expert panel (n = 35) was then formed consisting of orthopedic surgeons, anesthesiologists, chronic pain physicians, primary care physicians, pharmacists, registered nurses, physiotherapists, and clinical psychologists. Each expert provided up to three pain management recommendations for each of the presurgery, intraoperative, inpatient postoperative, and postdischarge periods. These preliminary recommendations were reduced, refined, and sent to the expert panel and "current state" survey respondents to create a consensus document using a Delphi process conducted from September to December 2020.

RESULTS

One thousand four hundred and five preliminary statements were summarized into 51 statements. Strong consensus (≥ 80% respondent agreement) was achieved in 53% of statements including the following: postsurgical opioid use risk should be assessed preoperatively; opioid-naïve patients should not start opioids preoperatively unless non-opioid multimodal analgesia fails; and if opioids are prescribed at discharge, patients should receive education regarding importance of tapering opioid use. There was no consensus regarding opioid weaning preoperatively.

CONCLUSIONS

Using multidisciplinary experts and a Delphi process, strong consensus was achieved in many areas, showing considerable agreement despite limited evidence for standardized pain management in patients undergoing complex elective foot and ankle surgery. No consensus on important issues related to opioid prescribing and cessation highlights the need for research to determine best practice.

Targeting Affective Mood Disorders With Ketamine to Prevent Chronic Postsurgical Pain

The phencyclidine-derivative ketamine [2-(2-chlorophenyl)-2-(methylamino)cyclohexan-1-one] was added to the World Health Organization's Model List of Essential Medicines in 1985 and is also on the Model List of Essential Medicines for Children due to its efficacy and safety as an intravenous anesthetic. In sub-anesthetic doses, ketamine is an effective analgesic for the treatment of acute pain (such as may occur in the perioperative setting). Additionally, ketamine may have efficacy in relieving some forms of chronic pain. In 2019, Janssen Pharmaceuticals received regulatory-approval in both the United States and Europe for use of the S-enantiomer of ketamine in adults living with treatment-resistant major depressive disorder. Pre-existing anxiety/depression and the severity of postoperative pain are risk factors for development of chronic postsurgical pain. An important question is whether short-term administration of ketamine can prevent the conversion of acute postsurgical pain to chronic postsurgical pain. Here, we have reviewed ketamine's effects on the biopsychological processes underlying pain perception and affective mood disorders, focusing on non-NMDA receptor-mediated effects, with an emphasis on results from human trials where available.

Protocol for the Ketamine for Postoperative Avoidance of Depressive Symptoms (K-PASS) feasibility study: A randomized clinical trial

Background: Postoperative depressive symptoms are associated with pain, readmissions, death, and other undesirable outcomes. Ketamine produces rapid but transient antidepressant effects in the perioperative setting. Longer infusions confer lasting antidepressant activity in patients with treatment-resistant depression, but it is unknown whether a similar approach may produce a lasting antidepressant effect after surgery. This protocol describes a pilot study that will assess the feasibility of conducting a larger scale randomized clinical trial addressing this knowledge gap. Methods: This single-center, double-blind, placebo-controlled pilot trial involves the enrollment of 32 patients aged 18 years or older with a history of depression scheduled for surgery with planned intensive care unit admission. On the first day following surgery and extubation, participants will be randomized to an intravenous eight-hour infusion of either ketamine (0.5 mg kg -1 over 10 minutes followed by a continuous rate of 0.3 mg kg -1 h -1) or an equal volume of normal saline. Depressive symptoms will be quantified using the Montgomery-Asberg Depression Rating Scale preoperatively and serially up to 14 days after the infusion. To detect ketamine-induced changes on overnight sleep architecture, a wireless headband will be used to record electroencephalograms preoperatively, during the study infusion, and after infusion. The primary feasibility endpoints will include the fraction of patients approached who enroll, the fraction of randomized patients who complete the study infusion, and the fraction of randomized patients who complete outcome data collection. Conclusions: This pilot study will evaluate the feasibility of a future large comparative effectiveness trial of ketamine to reduce depressive symptoms in postsurgical patients. Registration: K-PASS is registered on ClinicalTrials.gov: NCT05233566; registered February 10, 2022.